Re: [PATCH v2] x86/mce: work around an erratum on fast string copy instructions.

[Jue Wang]

On Fri, Feb 18, 2022 at 9:16 AM Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> On Fri, Feb 18, 2022 at 08:21:36AM -0800, Jue Wang wrote:
> > My concern was that here returns 0 instead the value read from the msr.
>
> You'd walk into that code only if you're doing MCE injections. In that
> case, it won't read or write MSR_IA32_MISC_ENABLE because the injection
> code writes into the injection mce struct only.
>
> So it won't disable fast strings when you manage to inject the exact
> error type which triggers this erratum.
>
> I think that's actually a good thing - you don't want to disable fast
> strings just because you injected a particular MCE type.

Ok, makes good sense.

Thanks Boris!

-Jue
>
>
> --
> Regards/Gruss,
>     Boris.
>
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